Hydraulic line assembly

ABSTRACT

A hydraulic tube and hose assembly for use on a crane having a telescoping boom. The assembly includes a coaxial hydraulic conduit mounted for travel with the extending arm of the boom and slidably connected to the non-extending portion of the boom. The coaxial conduit is of a length greater than the throw of the telescoping boom, so that upon extension of the telescoping arm, the conduit travels along with an generally parallel to the arm. The forward end of the coaxial hydraulic conduit is connected to a hydraulically operated implement mounted on the end of the boom, while the rearward end of the conduit is connected to a pair of flexible hydraulic lines leading to a stationary portion of the crane and ultimately to a hydraulic fluid supply. The flexible hydraulic lines define a curve of 180* which migrates during extension of the boom from a rearward position adjacent the end of the conduit to a forward position adjacent a line divider guide, thereby reducing the probability of injury to the hydraulic line and providing a determined course of travel for the hydraulic line during extension and retraction of the boom.

United States Patent [1 1 Dunbar [4 1 July 8,1975

[ HYDRAULIC LINE ASSEMBLY 221 Filed: Dec. 26, 1973 [21] Appl. No.:427,986

[52] US. Cl 137/615; l37/355.l7 [51] Int. Cl Bh /36 [58] Field ofSearch..... 137/355.16, 355.17, 355.18, l37/355.19, 355.20, 355.22,355.23, 355.24, l37/355.25, 355.26, 355.27, 355.28, 615, 344; 285/133,134; 239/ Primary ExaminerCharles .1. Myhre Assistant Examiner-Ira S.Lazarus Attorney, Agent, or Firm--Richard D. Emch; Thomas M. Freiburger[57] ABSTRACT A hydraulic tube and hose assembly for use on a cranehaving a telescoping boom. The assembly includes a coaxial hydraulicconduit mounted for travel with the extending arm of the boom andslidably connected to the non-extending portion of the boom. The coaxialconduit is of a length greater than the throw of the telescoping boom,so that upon extension of the telescoping arm, the conduit travels alongwith an gener ally parallel to the arm. The forward end of the coaxialhydraulic conduit is connected to a hydraulically operated implementmounted on the end of the boom, while the rearward end of the conduit isconnected to a pair of flexible hydraulic lines leading to a stationaryportion of the crane and ultimately to a hydraulic fluid supply. Theflexible hydraulic lines define a curve of which migrates duringextension of the boom from a rearward position adjacent the end of theconduit to a forward position adjacent a line divider guide, therebyreducing the probability of injury to the hydraulic line and providing adetermined course of travel for the hydraulic line during extension andretraction of the boom.

6 Claims, 9 Drawing Figures @AIEETFDJUL 8 ms SHEET 1 HYDRAULIC LINEASSEMBLY BACKGROUND OF THE INVENTION The invention relates toconstruction or other equipment having an extendable outer arm and moreparticularly to cranes having telescoping booms to which are mountedhydraulically operated equipment.

Cranes with telescoping booms which carry hydraulically operatedimplements generally employ flexible fluid lines to connect thehydraulic implements with a stationary hydraulic supply, for example, ahydraulic fluid pump. The lines traversing the telescoping boom must beof sufficient length to accommodate the fully extended telescoping arm.When the arm is partially or fully retracted, however, excess line isaccumulated. Because the line cannot be allowed to hang loosely belowthe boom and catch on objects when the crane is in use, excess line mustbe stored somewhere in or on the boom. Existing storage arrangementsgenerally result in wear and ultimate breaks in the flexible lines. Thisis due in part to the fact that the lines must slide along thenon-extending portion of the boom in order to feed the extending arm andin part to the inevitable doubling up and rubbing of the line in variousplaces along the line storage area as the boom is retracted.

In addition, the flexible lines on the extended telescoping arm aresubjected to damage by contact with, for example, boxes or other objectsbeing transferred by the crane implement.

SUMMARY OF THE INVENTION The present invention provides a telescopingboom hydraulic line assembly which reduces problems of line wear andbreakage inherent in many prior art line arrangements. The assemblyincludes a storage chamber defined along the non-extending portion ofthe telescoping boom. Rigid hydrualic lines from a hydraulic sourceextend the majority of the length of the chamber, terminating infittings aimed rearwardly. Flexible lines lead from these fittings to aconnection at the rearward end of a rigid coaxial hydraulic conduitpipe.

In the telescoping booms retracted position, the coaxial conduit pipeextends substantially through the length of the storage chamber, througha slide mounting at the forward end of the chamber, and to the end ofthe telescoping arm of the boom, where it is rigidly mounted. From here,flexible lines connect the conduit with the hydraulically operatedimplement at the end of the boom.

In the retracted position of the boom, a gradual 180 bend is formed inthe flexible line adjacent its connection with the rigid coaxialconduit. As the arm is telescoped forward, this bend advances forward athalf the rate of the arm, taking up line which has previously been lyingat rest in the storage chamber. When the boom is fully extended, theposition of the bend is approximately mid-way along the length of thestorage chamber. To prevent rubbing together of portions of the flexibleline as the conduit approaches its full forward position, alongitudinally extending guide shield mounted within the chamberprevents the upper portion of the folded flexible lines from contactingthe lower portion. The hydraulic tube and line arrangement of thepresent invention thus minimizes contact between portions of theflexible line, minimizes sliding contact of the lines with the storagechamber, and provides a rigid, slidably mounted tubular conduit wherethe lines must extend forward to accommodate the movement of thetelescoping arm of the boom. Minimum friction is generated duringextension and retraction of the telescoping boom.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is an elevational view of atruck mounted crane with a telescoping boom employing apparatusaccording to the present invention;

FIG. 2a is the right half of an enlarged, partially broken away view ofthe telescoping boom of FIG. I;

FIG. 2b is the left half of the same enlarged view;

FIG. 3 is a sectional view taken along the line 33 of FIG. 2a;

FIG. 4 is a fragmentary plan view taken along the line 44 of FIG. 20;

FIG. 5 is a sectional view taken along the line 5-5 of FIG. 2b;

FIG. 6 is a sectional view of a coaxial conduit taken along the line 66of FIG. 2b;

FIG. 7 is a cut away view of the telescoping boom partially extended;and

FIG. 8 is a cut away view of the telescoping boom fully extended.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. I of thedrawings, a truck 10 is indicated having a crane mechanism generallyindicated by the reference number 11. The crane 11 includes a firstpivotal boom 12 to which is connected a telescoping boom 13. Thetelescoping boom 13 includes a base or non-extending portion 14 and atelescoping arm I6. On the arm 16 is an end 17 to which is attached ahydraulically operated implement 18. Hydraulic controls 19 regulate theflow of hydraulic fluid from a hydraulic supply including well knownpumps and reservoirs (not shown). The hydraulic fluid passes throughhydraulic lines 2], 22, and 23 to the implement 18.

Referring now to FIGS. 20 and 2b, the telescoping boom is shown in anenlarged, detailed view. A boom housing 24 receives the telescoping arm16. Mounted to the side of the boom housing 24 is an outer housing 26which defines a storage chamber 27.

FIGS. 2a and 2b show the telescoping boom 13 in its fully retractedposition. In such position, a coaxial hydraulic conduit 30 extends fromthe rearward end of the chamber 27 through the length of the chamber 27and through a slide bearing 31 to a fixed connection 32 on thetelescoping arm I6. As the telescoping arm 16 is extended, the coaxialconduit 30 slides through the slide bearing 31, which preferably has alubricated bearing surface 33, best seen in FIG. 3. A pair of rigidhydraulic lines 34 lead from external hydraulic lines 21 through thegreater part of the length of the chamber 27, bend to a rearwarddirection, and terminate in fittings 36. Connected to the fittings 36are flexible hydraulic lines 37 and 38 which are preferably attached toone another. In the fully retracted position of the telescoping boom asindicated in FIGS. 2a and 2b, the flexible lines 37 and 38 extend backsubstantially linearly, then through 180 curves 39 and 40 to fittings 41and 42 on the coaxial conduit 30. A guide shield 43 having an angledrearward leg 44 provides boundaries of the area in which the flexiblelines 37 and 38 may rest.

FIG. 7 indicates the positions of the conduit 30 and the lines 37 and 38as the telescoping arm 16 of the boom 13. is extended forward. The bends39 and 40 in the flexible lines 37 and 38 advance forward in the storagechamber 27 at one-half the rate of advancement of the conduit pipe 30and telescoping arm 16. Sliding friction between the lines 37 and 38 andthe stationary portions of the storage chamber 27 is minimized. Aforward longitudinally-extending line guide shield 45 provides a dividerbetween the upper portions of the folded flexible lines 37 and 38 andtheir lower portions. thus minimizing friction between portions of thelines themselves.

FIG. 8 shows the conduit 30 and flexible lines 37 and 38 in the fullyextended position of the telescoping arm 16. The bends 39 and 40 in theflexible lines 37 and 38 have advanced to a position adjacent the end ofthe forward guide shield 45, and the major portions of the lines 37 and38 lie in substantially linear position above the shield 45. Somefriction is encountered as the lines 37 and 38 are drawn over the lineguide 45, but this friction is minimal.

FIG. 4 shows a portion of the telescoping boom 13 in plan view,indicating that hydraulic line assemblies according to the presentinvention may be mounted on both sides of the telescoping boom 13, whenadditional hydraulic lines are needed to operate equipment mounted onthe end of such a boom. On both sides of the boom housing 24 would be anouter housing 26, a coaxial hydraulic conduit 30, a connection 32 to thetelescoping arm 16 and a slide bearing 31.

FIG. also indicates, in section, a telescoping boom 13 having dualhydraulic line assemblies. Outer housings 26, coaxial conduits 30, linestorage chambers 27, hydraulic lines 37 and 38, and line guide shields43 and 45 are shown on both sides of the boom housing 24.

FIGS. 3 and 6 show details of construction of the slide bearing 31 andthe coaxial hydraulic conduit 30 which slides within the bearing 31. Thebearing 31 is preferably welded to a form fitted slot 46 in a length ofchannel 47 and is mounted to the boom housing 24 by means of bolts 48.Bolts 49 connect the outer housing 26 to the opposite flange of thechannel 47. The hear ing 31 comprises an outer sleeve 51 and an innersleeve 52 defining the lubricated inner bearing surface 33 which guidesthe coaxial conduit 30. A set screw 53 retains the inner sleeve 52within the outer sleeve 51. As seen in FIGS. 3 and 6, the coaxialconduit 30 comprises an outer tube 56 and an inner tube 54, which aresealed at points 55.

The above described preferred embodiment provides a hydraulic lineassembly which minimizes wear on hydraulic lines leading tohydraulically operated implements at the end of a telescoping boom. Theassembly is simple, economical to manufacture and virtually troublefree. Various other embodiments and alterdent fluid transfer conduits.said rigid conduit as- V sembly having its forward end attached adjacentthe forward end of such movable arm and its rearward end slidablymounted on such base section,

a plurality of flexible conduits positioned adjacent such base section,said flexible conduits having forward ends attached to and in fluidcommunication with said independent fluid transfer conduits, their otherends being in communication with the fluid supply source, and

a housing positioned on the exterior of the nonextending base section,said housing defining a chamber for receiving said flexible conduits andstationary divider means mounted within said housing for maintainingseparation between portions of said flexible conduits during extensionand retraction of the movable arm.

2. A hydraulic line assembly according to claim 1 wherein saidstationary divider means commprises a longitudinally extending shieldhaving a first end connected to said non-extending base section andwithin said housing and a second end spaced from said first end wherebysaid shield separates folded portions of said flexible conduit withinsaid housing.

3. The hydraulic assembly of claim 2, including guide means for slidablyretaining said rigid conduit assembly adjacent said base portion, saidguide means comprising a bearing rigidly mounted to said non-extendingbase section, said bearing slidably receiving said rigid conduitassembly.

4. The hydraulic line assembly of claim 2 wherein said rigid conduit, ina fully retracted position of the movable arm, extends approximately thelength of the base portion.

5. Apparatus according to claim 2 wherein said rigid conduit comprisesconcentric tubes.

6. The apparatus according to claim 2 wherein said plurality of flexibleconduits are bound together substantially throughout their length.

1. A hydraulic line assembly for use on an extensible boom having afluid supply source, a non-extending base section and a movable armsection extending outwardly from said base section, said assemblycomprising, a rigid conduit assembly having at least two independentfluid transfer conduits, said rigid conduit assembly having its forwardend attached adjacent the forward end of such movable arm and itsrearward end slidably mounted on such base section, a plurality offlexible conduits positioned adjacent such base section, said flexibleconduits having forward ends attached to and in fluid communication withsaid independent fluid transfer conduits, their other ends being incommunication with the fluid supply source, and a housing positioned onthe exterior of the non-extending base section, said housing defining achamber for receiving said flexible conduits and stationary dividermeans mounted within said housing for maintaining separation betweenportions of said flexible conduits during extension and retraction ofthe movable arm.
 2. A hydraulic line assembly according to claim 1wherein said stationary divider means commprises a longitudinallyextending shield having a first end connected to said non-extending basesection and within said housing and a second end spaced from said firstend whereby said shield separates folded portions of said flexibleconduit within said housing.
 3. The hydraulic assembly of claim 2,including guide means for slidably retaining said rigid conduit assemblyadjacent said base portion, said guide means comprising a bearingrigidly mounted to said non-extending base section, said bearingslidably receiving said rigid conduit assembly.
 4. The hydraulic lineassembly of claim 2 wherein said rigid conduit, in a fully retractedposition of the movable arm, extends approximately the length of thebase portion.
 5. Apparatus according to claim 2 wherein said rigidconduit comprises concentric tubes.
 6. The apparatus according to claim2 wherein said plurality of flexible conduits are bound togethersubstantially throughout their length.